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Abstract The origin of MXene's excellent electromagnetic shielding performance is not fully understood. MXene films, despite being inhomogeneous at the nanometer scale, are often treated as if they are compared to bulk conductors. It is reasonable to wonder if the treatment of MXene as a homogeneous material remains valid at very small film thickness and if it depends on the interlayer spacing. The goal of the present work is to test if the homogeneous material model is applicable to nanometer‐thin Ti3C2TxMXene films and, if so, to investigate how the model parameters may depend on variations in MXene interlayer spacings. MXene films containing flakes with interlayer spacing between 1.9 and 5.5 Å have been prepared using various intercalating agents. It is shown that modeling the films as being homogeneous agrees with experimental tests in the microwave frequency range. Microwave conductivity and dielectric constant parameters are estimated for the homogeneous film model by fitting measured results. The direct current (DC) conductivity matches the estimated microwave conductivity on the order of magnitude. A highly effective dielectric constant provides a good fit for the lower conductivity MXene films. Optical absorption agrees with the homogeneous material model of thin films as well.
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This content will become publicly available on November 27, 2025
Intercalation of Polyacrylonitrile Nanoparticles in Ti 3 C 2 T x MXene Layers for Improved Supercapacitance
We report the intercalation of polyacrylonitrile nanoparticles in Ti3C2Tx MXene layers through simple sonication. The use of polyacrylonitrile, which was synthesized via radical polymerization, offered dual benefits: (1) It increased the interlayer spacing of MXene, thereby exposing more surface area and enhancing ion transport channels during charge and discharge cycles, and (2) Integrating MXene with polyacrylonitrile enables the creation of a composite with conductive properties, following percolation principle. X-ray diffraction analysis showed an increase in the c-lattice parameter, indicative of the interlayer spacing, from 22.31 Å for the pristine MXene to 37.73 Å for the MXene−polyacrylonitrile composite. The intercalated polyacrylonitrile nanoparticles facilitated the delamination by weakening the interlayer interactions, especially during sonication. Electrochemical assessments revealed significant improvement in the properties of the MXene−polyacrylonitrile composite compared to the pristine MXene. The assembled asymmetric device achieved a good specific capacitance of 32.1 F/g, an energy density of 11.42 W h/kg, and 82.2% capacitance retention after 10,000 cycles, highlighting the practical potential of the MXene−polyacrylonitrile composite.
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- Award ID(s):
- 1800795
- PAR ID:
- 10562233
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Materials & Interfaces
- Volume:
- 16
- Issue:
- 47
- ISSN:
- 1944-8244
- Page Range / eLocation ID:
- 64784 to 64796
- Subject(s) / Keyword(s):
- MXenes polymer nanocomposites supercapacitor energy storage
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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